Finite-lattice expansion for quantum spin chains Article

Narayanan, R, Singh, RRP. (1990). Finite-lattice expansion for quantum spin chains . PHYSICAL REVIEW B, 42(16), 10305-10310. 10.1103/PhysRevB.42.10305

cited authors

  • Narayanan, R; Singh, RRP

authors

abstract

  • We investigate the thermal properties of s=1/2 and 1 antiferromagnetic Heisenberg spin chains by an expansion in finite lattices. The expansion is based on expressing the quantity of interest, in the thermodynamic limit, as a sum over contributions from different length scales. The first few terms in the expansion, obtained by diagonalizing chains of length up to 13 for s=1/2 and length up to 9 for s=1, provide an accurate estimate for the internal energy and specific heat for T/J 0.25 and 0.35, respectively. At lower temperatures, by studying the exponential decay of the various terms in the expansion, we estimate the correlation length . We get good estimates for down to T/J=0.06 for s=1/2 and T/J=0.02 for s=1. We find that for s=1 increases much more slowly than for s=1/2 and is consistent with a value of 7 at T=0. © 1990 The American Physical Society.

publication date

  • January 1, 1990

published in

Digital Object Identifier (DOI)

start page

  • 10305

end page

  • 10310

volume

  • 42

issue

  • 16